A Summoner's Guide to Demons
by ninemelodies
Summary: Zexion didn't mean to summon Demyx. He didn't mean to become friends with him. He didn't mean to let him stay this long, but things don't always work out the way you want them to.


" _A Summoner's Guide to Demons_ , huh?" Zexion scoffed slightly, setting the book down at his library table. He brushed more dust off of the books front cover, revealing a very ornate picture. It was colorful and detailed, that much was sure, but Zexion couldn't make out what the picture was of in the dim lighting.

Not that it mattered. Even with such a beautiful cover, he knew it was full of bullshit. Demons didn't exist, after all. Even so, something nagged at the back of his mind, whispering that he should open the book. He lifted the edge of the front cover slightly and hesitated. He was sure he'd heard laughter, but he knew he was alone, tucked into the obscure and forgotten section of the town's local library.

Shrugging it off, he opened the book all the way and began to skim through its pages. He wasn't actually reading, just glancing through the book in the hopes that something interesting would appear. After getting through the do's and don'ts of summoning demons, he finally reached the section of the book that actually gave information about the demons that could be summoned. Most of them seemed fairly normal, evil and violent, do not summon, except for the last one. This demon's name was Demyx and judging from his description, he seemed to be the kindest and most level headed of the lot. Zexion had decided. To prove that demon's didn't exist, and therefore couldn't be summoned, he was going to attempt to summon this…Demyx demon. And so late that night he did just that. As in, he actually got Demyx to appear.

Zexion stayed sitting, eyes widening in shock as he took in the new person suddenly standing in his room. It was the demon that broke the silence. "So…you summoned me, yeah? Whatcha need?" So far the description in the book seemed to be right. Demyx looked pretty much human, from his hair to his clothes; the only thing about him that screamed unhuman was his eyes. They were solid black. Zexion found it unsettling, and couldn't keep eye contact for long.

"I didn't actually think the summoning would work," Zexion muttered, finally picking himself off of the floor. Even standing, he was still shorter than Demyx. Of course, the fact that Demyx was floating a couple of inches off the floor could've had something to do with that.

"So you just…summoned me as a joke?" Demyx's brows crinkled, as if he was trying really hard to understand why anyone in their right mind would do that.

"No! I just…was trying to prove that demon's didn't exist." He felt kind of stupid, saying that to someone that was very obviously not human and was very obviously a demon.

"Well we do exist, and now you've got one in your house. What to do about that, hm?" Demyx flipped over onto his back and floated lazy circles around Zexion's head. A sly grin snuck its way across his face. He was very much enjoying the way the human refused to look him in the eyes. Blinking once, he felt the way his eyes shifted into a much more human looking set.

Zexion turned around, prepared to ask the demon something, but the new set of eyes staring at him made him stop. "You can change your appearance?"

Demyx scoffed, "You think I look like this normally? If I was in my true form you'd jump right out of your skin." He shrugged. "I mean I could show it to you, if you wanted but…" He grinned, and this time it wasn't friendly. It was a menacing grin, all fangs and no hint of amusement.

"That's okay…" Zexion shivered slightly as the cold tingling of fear slid down his spine. He had gotten himself into some deep trouble, and now he had to get himself out of it. "Can't I just unsummon you? I didn't have anything I wanted you to do."

Just as quick as it had changed before, Demyx's smile morphed back into something warm and easygoing. "It doesn't work quite like that, at least, as far as I'm aware it doesn't work like that." He stopped hovering and let his feet touch the ground. "See," he walked forward a step to poke Zexion's forehead, "You are supposed to give me a task to complete. Could be anything ranging from kill this person to find my lost cat, but I have to do it. Only after I do it can I leave. See the issue here?" Demyx backed up again. "You don't have a task for me to complete so I'm stuck here in limbo till you think of one. Or until you find a different way to get rid of me, whichever comes first."

Zexion kept quiet as he tried to think of a task to give to the demon. Anything, it could even be something simple, but hard as he tried, he couldn't come up with anything. Zexion didn't need anything done because he did everything on his own. Finally he thought of one, "Keep me safe until I find some way to get rid of you."

Demyx's eyes flashed and that menacing grin returned. "Deal."

It took a week of prodding on Demyx's part before Zexion finally told the demon his name. "Zexion," Demyx had said, drawing it out, as if tasting the name. "I like it."

By the time two weeks had passed, Zexion had become so accustomed to the demon's presence that it was almost like he wasn't there. At least, it worked until Demyx made some annoyingly useless comment about the weather or the candy store down the street. For the most part, no one else noticed Demyx, and those that did tended to shy away from him. Even in a human form, there was something unsettling about the mulleted-blond. Zexion hardly noticed it anymore, and at night he slept peacefully knowing that Demyx _had_ to protect him until Zexion could finally get rid of him.

Three weeks after Zexion had summoned Demyx; he finally caved and took the demon to the candy shop down the street. After forcing the demon to swear he would behave and not cause mischief, Zexion opened the door to the sugary heaven. Demyx had walked in slowly, eyes wide as he took in all the sights of the brightly colored store. Next he had taken a deep breath before wandering off towards the chocolate section of the store. Zexion picked up a bag of caramel hard candies before following the demon. He wasn't expecting to see the demon with his face pressed against the chocolate display, much resembling a small child. Smiling slightly, Zexion stepped closer and tapped Demyx on the shoulder. When he was sure the blond was paying attention to him, he spoke. "You can choose two things, but that's all I have the money for." Demyx's face lit up and he hurriedly picked the chocolate that he wanted. Zexion was slightly surprised that there was still some left when they made it back to the apartment.

A month had passed by this point, and something in the back of Zexion's mind told him it was dangerous to get this close to a demon, to put this much trust in something that was supposed to be evil and violent. He pushed that something into a corner and mentally slammed a door on it.

It was the sixth month mark when Demyx started getting restless. Zexion would wake up in the middle of the night to find the blond staring at him, something swirling in Demyx's eyes that he didn't recognize. It frightened him enough that he tricked Demyx into staying at the candy shop while he went back to library. He headed back to the corner he'd been in when he first found the book that started this entire mess. Pulling the book from the shelf, he settled back into the chair and flipped to the section about Demyx. There wasn't much to go on, and what he had just said that Demyx was kind, wouldn't hurt a fly, and things of the like. When he recalled the way the blond's eyes looked the night before, he repressed a shiver. Demyx was hiding something, Zexion just didn't know what.

Zexion continued reading, not finding anything. By the time he finished the book, two hours had passed and he was sure Demyx was looking for him. He moved his hand to close the book when he noticed something hurriedly scrawled on the back end sheet of the book. There in the center of the page, someone had written a message. _Do not summon the heart eater! The blond is a liar._ As far as Zexion could remember, Demyx was the only demon that had blond hair in his human form. He flipped back to the section on the blond demon and began examining the page even closer. There, up at the top, where it gave the title of the demon, something had been ripped out. At first glance, Demyx's title was 'The Heart,' but now Zexion wasn't quite so sure.

Something brushed the back of his neck and he flinched as a hand slammed the book he was reading shut. He looked up, making eye contact with the very demon he'd been reading about. Demyx's eyes were cold and that unsettling, menacing smile was back. This time it was tainted with something else, as if he were trying to make it look sweeter than it was. "Whatcha reading?" He asked, voice low and dripping honey. Demyx's sudden presence tipped off all of Zexion's warning signals.

The voice that had warned him earlier was back, except now it was telling him to run. Once again, he pushed it back and gave the blond a hesitant smile. "I was just reading about how else to get rid of a demon." Demyx could see right through his lie, and Zexion knew it. However after a full minute of a silent stare down, the blond let it go. He shifted gears again, and suddenly the easy going personality Zexion was used to was back and present. It was as if the Demyx who had slammed the book closed didn't exist.

"So what did you find?" The blond ask, settling down into a chair next to Zexion. He had his feet up on the table and looked relaxed as could be, but Zexion sensed tenseness in the way the demon moved.

"I hadn't yet…" Zexion opened the book again, making sure to avoid the page with information about Demyx. There was only one section he hadn't read, so he flipped there, praying to whatever god was listening that it would help him get rid of the blond next to him. There, on the very front page, were clear instructions on how to summon and get rid of a demon. He skimmed over it quickly, making sure to memorize every step before he flipped to the next page. If Zexion was being honest with himself, he would've said that he didn't want the demon to leave. Demyx's presence had become just a normal thing in his life that Zexion didn't want him to go. The world would feel empty without the demon that had infested his home and life.

So Zexion kept the instructions a secret for the next three months. By this time, he had grown comfortable with the demon once again, and the events that had occurred at the library were just a shadow of a memory.

Even Demyx admitted that it would be weird to go home after all this time. He had grown used to the human, and his weird ways. Every day, before Zexion got home from work, he would go pick up a bag of the caramel hard candies he knew the human liked. One day, he even added a bouquet of the human had been talking about.

One more month passed before Zexion came clean about the instructions he'd found that day in the library. At first, Demyx had looked confused, but then his face had smoothed over. Suddenly, he began to laugh. "You…you stupid human, I knew the deal had been completed the second you read those instructions!" By now Demyx was on the floor in a hysterical fit. Had he been human, he would've died from lack of oxygen.

Confusion rippled across Zexion's face. "You knew? Then why are you still here? The deal was completed right, you could've left." For a second Zexion let himself believe that it was because the demon actually cared about him.

Demyx's next word's shattered any hope he may have had. "And you even believed I cared about you!" The blond sat up, wiping away a nonexistent tear. When his eyes opened again, they were pitch black. "I never cared about you. I was leading you on, and you fell for it, hook, line, and sinker!"

Zexion's hope crumbled, and from the ashes rose a new feeling. Hatred. He hated this demon with all every fiber of his being. Hated himself for ever believing that a demon was capable of caring. Hated himself for being a puppet in the demon's plans.

By now Demyx was standing and that menacing grin was back. His face was shifting, something was growing from his temples and Zexion could see movement from behind the demon. When he flicked his eyes back to the demon's face, there were horns and fangs where there used to be only smooth skin and perfect human teeth. This wasn't the demon's true form, Zexion knew that, but it was close.

"You want to know why I stayed?" Demyx was walking circles around Zexion like a hunter observing their prey. "I stayed because it was too easy. That book you found? It lies. The person who wrote it summoned each of those demons in turn. Amazingly, they survived to reach me. I lied to them too. Made them believe that I was the nice one of the demons, the kind one. Then I betrayed him, twisted that trust into hatred." Demyx's grin widened. "Then I ate his heart, just like I will with yours."

Demyx stalked forward, moving with an inhuman grace and speed. Suddenly Zexion was against the wall and he could feel claws tapping on his chest. "You see, I'm the heart eater that book warned you about." Then he began to push his claws into the human's chest, tearing through fragile skin and muscle without even trying.

Zexion's mind raced, trying to stay ahead of the numbing pain. He knew how to unsummon Demyx, maybe if he could do it fast enough. He opened his mouth to begin chanting when suddenly his mind went blank. Demyx had reached his goal. He drew his hand back, bringing back with it a warm, bloody heart. He grinned and crouched down next to the human's dead body, "What is it you humans say? Oh, I remember. Thank you for the meal." And then he began to eat.


End file.
